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Rafael Nadal beat John Isner on Sunday for his first-ever title at the Western & Southern Open. (Jim Owens/Icon SMI)

MASON, Ohio -- Rafael Nadal finally broke through at the Western and Southern Open to win the tournament for the first time in his career, beating John Isner 7-6 (8), 7-6 (3) in Sunday's men's final to capture his 26th ATP Masters 1000 title. But top-ranked Serena Williams was unable to join him in the first-time winner's circle, losing to No. 2 Victoria Azarenka 2-6, 6-2, 7-6 (6) in the women's final.

With his Cincinnati win, Nadal extended his hard-court winning streak to 15-0 this season, winning three hard-court ATP Masters 1000 tournaments and he's the first man to win both Montreal and Cincinnati back-to-back since Andy Roddick in 2003. That year, Roddick went on to win the U.S. Open three weeks later. But Nadal isn't one to prognosticate about his chances at the U.S. Open, where he'll go in as the favorite.

"If you ask me which way you want to enter the US Open, I will tell you that's the perfect way to enter the US Open," he said. "But that doesn't mean that I'm going to play a great US Open. Only thing it really means is I was playing great during these two weeks."

Nadal will rise to No. 2 in the rankings, an incredible achievement considering he didn't play the U.S. Open, Australian Open, and the ATP World Tour Finals due to the knee injury that ruled him out for seven months. Returning to the tour in February, Nadal has made the finals of 11 of 12 tournaments, winning nine of them. The rankings move is an important one, as it means Nadal will go into the U.S. Open as the No. 2 seed placed on the opposite side of the draw from No. 1 Novak Djokovic.

Nadal will go into the U.S. Open with two key wins under his belt, after defeating top-ranked Djokovic in Montreal 6-4, 3-6, 7-6 (2) and Roger Federer 5-7, 6-4, 6-3 here. To get two tight wins over two of his primary rivals on hard courts speaks to his confidence level at the moment. He's now 53-3 on the season.

"Winning back‑to‑back tournaments is, first of all, difficult because, first thing, the courts are not exactly the same," Nadal said. This is the first time he's won back-to-back hard court tournaments in his career. "The weather conditions are not exactly the same. The rivals brings your body and your tennis to the limit. You need to be 100 percent focused during the two weeks and playing every day."

"So I was lucky. I was close to losing against Roger the other day. I was close to losing against Novak in Montreal. I was close today."

Indeed, despite the straight-set win, Nadal knows the match could have easily flipped the other way in favor of Isner. Unseeded for the tournament and into the final after beating three top 10 players, Isner executed his simple but effective game plan perfectly: hold serve, play out the tiebreak, and hope for the best. Nadal was unable to earn a single break point in the match, a testament to how well Isner served. When he had a chance to finally get one in the second set at 4-5, 0-30, Isner dug out of it to hold thanks to some gutsy hitting off his forehand side. The difference came down to just a handful of points, including a volley Isner bricked in the first set tiebreak to give Nadal the mini-break and a big backhand miss in the second set tiebreak to give Nadal the edge there.

"If I'm dialed in and I'm focused, I'm very tough to beat, no matter who I'm playing," Isner said after the losing in his second ATP Masters 1000 final. "So I expected a close match today. That's exactly what it was. A lot of those key points just didn't go my way, but I have absolutely nothing to complain about. I caught a lot of breaks this week, and sometimes that's just how it goes."

Here's Nadal saving a break point with a perfect sliding volley. Not much Isner can do about that.

http://youtu.be/pFbiCDRpTBQ

"I didn't face a break point against one of the greatest returners of all time. That's super encouraging. I went out there and did everything I could do to win the match. It just wasn't enough."

Isner walks away from the loss, his fourth to Nadal, with a bevy of confidence heading into the U.S. Open. Rising to No. 14 in the rankngs, he's scheduled to play the Winston-Salem Open next week in his home state of North Carolina. The conventional wisdom says he should take the week off to rest before the U.S. Open begins in a week but he says he hasn't made a decision yet. Isner has already played 20 matches this summer, more than any other ATP player. The only significant blemish on his post-Wimbledon results is a first round loss to Vasek Pospisil in Montreal. But even that might have been a blessing disguise.

"It gave me some time to rest up and come here and get ready to go. That's what I did, and I played extremely well all week. Thought I played well again today. Unfortunately, it just wasn't good enough. Going to hold my head up high after today's match and after this whole week."

Slim margins also defined the women's final, which saw Azarenka overcome a slow start to hand Williams just her fourth loss of the year. Behind her clutch returning and aggressive play, Azarenka out-competed Williams, who struggled to elevate her game from a general state of sluggishness. Despite not playing her best, Williams served for the match at 5-4 in the third set only to get broken. Then at 5-4 in the tiebreaker, Williams missed an easy backhand into the empty court that would have given her match points.

That mistake was the only reprieve Azarenka needed. At 6-6, Azarenka played a perfect volley after a long side-to-side rally that stood out as the point or the match and then she converted her second match point after Williams sent a forehand into the net.

Here's video of Azarenka's key volley:

http://www.youtube.com/watch?v=Y8T7NJ1v3Og&feature=youtu.be

It was a well-earned victory for Azarenka, who had not won a title since Doha. The win snapped Williams' 14-match win streak, though the defending U.S. Open champion didn't seem too concerned.

"It makes me more relaxed and almost happy that I lost because now I don't have to worry about every day someone asking me about some silly winning streak," Williams said after the match. "So maybe it was for the best."

Even with the loss, Williams still leads Azarenka 12-3 in their head-to-head but Azarenka has now won two straight hard-court finals over the American, having beaten her earlier this year in Doha. Despite the lospided head-to-head, Serena admits this is a rivalry, albeit a friendly one.

"We have good matches," she said after the loss. "We go against each other really tough. It's a good rivalry. I'm No. 1. She's No. 2. So we have that rivalry which consists of meeting in the final, which makes it even more so exciting. I personally was thinking it is a good rivalry and it's good to have someone out there that can play hard and fight so tough."